23 Commits

Author SHA1 Message Date
0e3cc46a41 Merge pull request 'Restructure the code and implement a printing queue' (#29) from restructure-printing-queue into master
Reviewed-on: #29
2026-05-27 00:00:56 +02:00
n07070
bbfe1936da Remove unused import 2026-05-26 23:58:47 +02:00
n07070
8134c5e892 Improve linting of printer class 2026-05-26 23:56:55 +02:00
n07070
934f766cf3 Update waiting time, update Exceptions 2026-05-26 23:53:26 +02:00
n07070
eb9e1ec200 Remove code meant for another branch ( brother-ql code ) 2026-05-26 23:50:00 +02:00
n07070
bc035508cd Update line lenght of docstring 2026-05-22 11:01:06 +02:00
n07070
cba34744f6 Update raspberry pi class to print via the print queue 2026-05-22 11:01:06 +02:00
n07070
0c8c40098c Add docstring & comments, remove dead code 2026-05-22 11:01:06 +02:00
n07070
3b640dc549 Add comments about the code structure 2026-05-22 11:01:06 +02:00
n07070
2daafe28f2 Apply linting 2026-05-22 11:01:06 +02:00
n07070
c50922790d Restructure main class to activate worker and use tasks, print queue,
update Printer
2026-05-22 11:01:06 +02:00
n07070
e8ec9b74c0 Restructure web class to use print queue and tasks 2026-05-22 11:01:06 +02:00
n07070
9dee67c333 Add worker class 2026-05-22 11:01:06 +02:00
n07070
42bf6d6496 Add printing queue objects 2026-05-22 11:01:06 +02:00
n07070
a38088bd05 Add task objects 2026-05-22 11:01:06 +02:00
n07070
cb3e0d900f Update numpy 2026-05-22 11:01:06 +02:00
n07070
c5a8019fbe Add an alert if the webcam print fails 2026-05-22 11:01:06 +02:00
n07070
e926ee9163 Update printing routes for the form 2026-05-22 11:01:06 +02:00
n07070
3f915a1b25 Fix error flashing and transmission 2026-05-22 11:01:06 +02:00
n07070
a06086521a Add new web route, restructure API route 2026-05-22 11:01:06 +02:00
n07070
ee27c62d0f Add new functions for discovery and parsing of printers, WIP 2026-05-22 11:01:06 +02:00
n07070
2a11239c1e Add new dependencies for brother ql printers 2026-05-22 11:00:43 +02:00
n07070
bd9888caf7 Downgrade python supported version for 3.13 2026-05-20 12:01:51 +02:00
10 changed files with 256 additions and 274 deletions

View File

@@ -79,6 +79,16 @@ Your contributions are very much welcome ! You can either request an account on
Please also say if you had a printer to test your code, and which printer you've been using.
### Code structure
The app is written about the Flask framework. You can start by looking at the code in the `src/` folder, in the `main.py` file. There, you will see that a few classes are initialized. In general, they are two parts to the program :
The Web pages and the API, which are the user-facing parts. This is with what the users will interact, and define how the program is going to be used. The web pages are renderer from the `include/` folder where Jinj2 templates are defined.
The Worker and Printer Queue are the internal parts. When a new thing needs to be printed, usually sent from the Web or API interfaces, a new Task in the type of the document is created, and added to a print queue. Then, a Worker thread looks up the state of the queue every so often and picks jobs to execute on the printers connected to the system.
The last part of the program is the Raspberry Pi class, that handles to Photomaton mode, which handles button presses, and LED indicator and a flash.
### Linting
If you want to contribute code, please make sure to lint the project before commiting. This helps the code keep a general structure, and avoids some commons erros and mistakes.

View File

@@ -7,7 +7,7 @@ authors = [
]
license = "AGPLv3"
readme = "README.md"
requires-python = ">=3.14"
requires-python = ">=3.13"
dependencies = [
"flask (>=3.1.3,<4.0.0)",
"numpy (>=2.3.4)",

View File

@@ -23,7 +23,6 @@ import sys
import os # For VARS from the shell.
import pprint # To pretty print JSON
import toml # Used for the config file parsing
import threading
from flask import (
Flask,
request,
@@ -43,7 +42,6 @@ from web import Web # Wrapper for the web routes and API
from print_queue import PrintQueue
from worker import PrintWorker
# We create the main Flask object
app = Flask(__name__)
socketio = SocketIO(app, cors_allowed_origins="*")
@@ -87,7 +85,7 @@ except FileExistsError:
app.logger.debug("Directory %s already exists.", UPLOAD_FOLDER)
except PermissionError:
app.logger.error("Permission denied: Unable to create %s", UPLOAD_FOLDER)
exit(77)
sys.exit(77)
# Output the config file
if os.getenv("FLASK_DEBUG"):
@@ -103,9 +101,6 @@ app.config["TEMPLATES_AUTO_RELOAD"] = True
# Printer connection
# Uses the class defined in the printer.py file
printer = Printer(app, 0x04B8, 0x0E28)
# printers = Printer(app)
# printers.discover_printers()
# printers.init()
printer.init_printer()
# Find out if we are running on a Raspberry Pi
@@ -124,19 +119,19 @@ RASPBERRY_PI_CONNECTED = rpi.is_raspberry_pi()
# Queue creation
print_queue = PrintQueue(app)
# Web & API routes
# Web & API management
web = Web(app, print_queue)
# Start worker thread
worker = PrintWorker(app, print_queue, printer, socketio)
worker.start()
# The rate limit
limiter = Limiter(
get_remote_address, app=app, default_limits=["1500 per day", "500 per hour"]
)
# General routes
@app.route("/")
@limiter.limit("1/second", override_defaults=False)
def index():
@@ -152,8 +147,8 @@ def webcam():
app.logger.debug("Loading webcam interface")
return render_template("webcam.html")
# Form treatement
# Form treatement
@app.route("/web/print/sms", methods=["POST"])
@limiter.limit("6/minute", override_defaults=False)
def web_print_sms():
@@ -164,7 +159,7 @@ def web_print_sms():
txt = request.form["txt"]
except werkzeug.exceptions.BadRequestKeyError as e:
app.logger.error("Whoops, we are missing the txt input field. : %s ", str(e))
flash("Whoops, no forms submitted or missing signature : " + str(e), 'error')
flash("Whoops, no forms submitted or missing signature : " + str(e), "error")
return redirect(url_for("index"))
try:
@@ -172,19 +167,19 @@ def web_print_sms():
sign = request.form["signature"]
except werkzeug.exceptions.BadRequestKeyError as e:
app.logger.warning(
"No signature found for this print, using default signature.", str(e)
"No signature found for this print, using default signature : %s ", str(e)
)
sign = configuration_file["defaults"]["signature"]
try:
web.print_sms(txt, sign)
except Exception as e:
except RuntimeError as e:
app.logger.error("Whoops, we could not print an SMS because : %s ", str(e))
flash("Whoops, we could not print an SMS because :" + str(e), 'error')
flash("Whoops, we could not print an SMS because :" + str(e), "error")
return redirect(url_for("index"))
# end try
flash("The SMS has been printed !", 'info')
flash("The SMS has been added to the print queue !", "info")
return redirect(url_for("index"))
@@ -199,7 +194,7 @@ def web_print_img():
sign = request.form["signature"]
except werkzeug.exceptions.BadRequestKeyError as e:
app.logger.warning(
"No signature found for this print, using default signature.", str(e)
"No signature found for this print, using default signature : %s", str(e)
)
sign = configuration_file["defaults"]["signature"]
@@ -207,7 +202,7 @@ def web_print_img():
if "img" not in request.files:
app.logger.error("Whoops, no images submitted : %s ", str(e))
app.logger.error("Error getting the files : %s", str(e))
flash("Whoops, no images submitted : " + str(e), 'error')
flash("Whoops, no images submitted : " + str(e), "error")
return redirect(url_for("index"))
file = request.files["img"]
@@ -215,20 +210,21 @@ def web_print_img():
# empty file without a filename.
if file.filename == "":
app.logger.error("Submitted file has no filename !")
flash("Submitted file has no filename !", 'error')
flash("Submitted file has no filename !", "error")
return redirect(url_for("index"))
try:
app.logger.debug("Sending the image to the printer.")
web.print_image(file, sign)
except Exception as e:
except RuntimeError as e:
app.logger.error("The image could not be printed because : %s ", str(e))
flash("The image could not be printed because : " + str(e), 'error')
flash("The image could not be printed because : " + str(e), "error")
return redirect(url_for("index"))
flash("Picture printed !", 'info')
flash("Picture added to the print queue !", "info")
return redirect(url_for("index"))
# API routes
# The api has the following methods
# api/print/{sms,img,letter,qr,barcode}
@@ -267,11 +263,12 @@ def api_print_sms():
try:
# comment: We try to print the SMS
web.print_sms(txt, sign)
except Exception as e:
except RuntimeError as e:
return str(e), 500
# end try
return "OK", 200
@app.route("/api/print/img", methods=["POST"])
@limiter.limit("6/minute", override_defaults=False)
def api_print_image():
@@ -293,8 +290,7 @@ def api_print_image():
return "No image submitted", 400
file = request.files["img"]
# If the user does not select a file, the browser submits an
# empty file without a filename.
# If the user submits an empty file without a filename.
if file.filename == "":
app.logger.error("Submitted file has no filename !")
return "Submitted file has no filename !", 400
@@ -302,45 +298,57 @@ def api_print_image():
try:
app.logger.debug("Sending the image to the printer.")
web.print_image(file, sign)
except Exception as e:
except RuntimeError as e:
return str(e), 500
return "OK", 200
@app.route("/api/camera/picture", methods=["GET"])
def camera_picture():
"""Returns a picture taken by the camera on a raspberry pi"""
if RASPBERRY_PI_CONNECTED:
try:
return rpi.camera_picture()
except Exception as e:
except RuntimeError as e:
return jsonify({"message": "Error getting the stream : " + e}), 500
else:
return jsonify({"message": "No camera present"}), 500
@app.route('/api/queue', methods=["GET"])
@app.route("/api/queue", methods=["GET"])
def api_queue_status():
"""API endpoint for entire queue"""
return jsonify(web.get_queue_state())
@app.route('/api/worker', methods=["GET"])
@app.route("/api/worker", methods=["GET"])
def api_worker_state():
"""API endpoint to get the worker state"""
return jsonify(worker.current_state())
@app.route('/api/worker/start')
@app.route("/api/worker/start")
def api_worker_start():
"""
Enable to worker. This starts to process the print queue.
"""
worker.start_worker()
return jsonify(worker.current_state())
@app.route('/api/worker/stop')
@app.route("/api/worker/stop")
def api_worker_stop():
"""
Stops the print queue. This stops the processing of the print queue.
"""
worker.stop_worker()
return jsonify(worker.current_state())
## Authentification
@app.route("/login")
@limiter.limit("1/second", override_defaults=False)
def login_page():
@@ -393,5 +401,6 @@ def camera_status():
else:
socketio.emit("camera_status", False)
if __name__ == "__main__":
app.run(debug=True, use_reloader=False, host="0.0.0.0", ssl_context="adhoc")

View File

@@ -1,6 +1,8 @@
# This class has the method by which we manage the Tasks
# It's a printing queue, so we need to add, remove and get information on where
# the queue is
"""
This class has the method by which we manage the Tasks
It's a printing queue, so we need to add, remove and get information on where
the queue is
"""
from collections import deque
@@ -9,12 +11,14 @@ from collections import deque
import threading
from datetime import datetime
from task import TaskType, CutTask
from task import TaskType
class PrintQueue:
"""
A Double-ended Queue to manage the printing Tasks
"""
def __init__(self, app):
self.app = app
self._queue = deque()
@@ -34,7 +38,11 @@ class PrintQueue:
self._queue.append(task)
position = self._queue.index(task)
# We return the current position of the task if it was added
self.app.logger.debug("Added a new task %s to the queue at position %s", task.task_id, position)
self.app.logger.debug(
"Added a new task %s to the queue at position %s",
task.task_id,
position,
)
return position
except Exception as e:
self.app.logger.error("Could not add a task to the queue : %s ", e)
@@ -85,32 +93,32 @@ class PrintQueue:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"type": task.task_type,
"position": index,
"in_queue": True,
"content" : task.content,
"signature": task.signature
"content": task.content,
"signature": task.signature,
}
if task.task_type == TaskType.TEXT:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"type": task.task_type,
"position": index,
"in_queue": True,
"image_path" : str(task.image_path),
"signature" : task.signature,
"process" : str(task.process)
"image_path": str(task.image_path),
"signature": task.signature,
"process": str(task.process),
}
if task.task_type == TaskType.CUT:
return {
"task_id": task_id,
"status": task.status,
"type" : task.task_type,
"type": task.task_type,
"position": index,
"in_queue": True
"in_queue": True,
}
return None
@@ -123,5 +131,5 @@ class PrintQueue:
"status": task_status,
"position": None,
"in_queue": False,
"completed_at": datetime.now().isoformat()
"completed_at": datetime.now().isoformat(),
}

View File

@@ -1,12 +1,18 @@
# Importing the module to manage the connection to the printer.
import escpos.printer
"""
This class manages connexion to a Printer
"""
# import brother_ql
from time import sleep, gmtime, strftime
from time import sleep
import os.path
from PIL import Image, ImageEnhance, ImageOps
from PIL import Image, ImageEnhance
import numpy as np
class Printer(object):
# Importing the module to manage the connection to the printer.
import escpos.printer
class Printer():
"""
# The connection is based on the ESC/POS library
@@ -27,7 +33,7 @@ class Printer(object):
ready = False
def __init__(self, app, device_id, vendor_id):
super(Printer, self).__init__()
super().__init__()
self.app = app
self.ready = False
self.printer = None
@@ -65,7 +71,7 @@ class Printer(object):
# TODO: This could happen directly when creating a new Printer class
if os.getenv("FLASK_DEBUG"):
waiting_elapsed = 15
waiting_elapsed = 3
else:
waiting_elapsed = 10
@@ -75,21 +81,26 @@ class Printer(object):
try:
# This also calls open(), which we need to close()
# or else the device will appear as busy.
p = escpos.printer.Usb(self.device_id, self.vendor_id, 0, profile="TM-P80")
except Exception as e:
self.app.logger.error(
"The USB device is not plugged in, trying again %s : %s",waiting_elapsed, str(e)
p = escpos.printer.Usb(
self.device_id, self.vendor_id, 0, profile="TM-P80"
)
except RuntimeError as e:
self.app.logger.error(
"The USB device is not plugged in, trying again %s : %s",
waiting_elapsed,
str(e),
)
pass
try:
if p.is_online():
self.ready = True
self.app.logger.debug("Printer online !")
except Exception as e:
self.app.logger.error("Error while getting the printer online %s : %s",waiting_elapsed, str(e)
except RuntimeError as e:
self.app.logger.error(
"Error while getting the printer online %s : %s",
waiting_elapsed,
str(e),
)
pass
sleep(1)
waiting_elapsed -= 1
@@ -128,8 +139,10 @@ class Printer(object):
def _print_sms(self, msg, signature="", bold=False):
if not isinstance(msg,str):
self.app.logger.error("It is not possible to print a " + str(type(msg)) + ", only strings.")
if not isinstance(msg, str):
self.app.logger.error(
"It is not possible to print a " + str(type(msg)) + ", only strings."
)
raise ValueError
# We make sure that the signature is not something too goofy
@@ -141,7 +154,7 @@ class Printer(object):
self.app.logger.warning(
"Could not print message of this length: " + str(len(clean_msg))
)
raise Exception(
raise RuntimeError(
"Could not print message of this length :"
+ str(len(clean_msg))
+ ", needs to be below 4096 caracters long."
@@ -151,7 +164,7 @@ class Printer(object):
self.app.logger.warning(
"Could not print signature of this length: " + str(len(clean_signature))
)
raise Exception(
raise RuntimeError(
"Could not print signature of this length :"
+ str(len(clean_signature))
+ ", needs to be below 256 caracters long."
@@ -168,7 +181,9 @@ class Printer(object):
self.printer.close()
except Exception as e:
self.app.logger.error("Unable to print because : " + str(e))
raise RuntimeError("Unable to print a SMS, the printer couldn't do it.") from e
raise RuntimeError(
"Unable to print a SMS, the printer couldn't do it."
) from e
self.app.logger.info("Printed text")
return True
@@ -193,7 +208,7 @@ class Printer(object):
+ str(path)
+ " wasn't found. Please try again."
)
else:
self.app.logger.debug("Printing file from " + str(path))
if process:
@@ -201,7 +216,9 @@ class Printer(object):
self.app.logger.debug("Proccessing the image")
path = _process_image(self, path)
except RuntimeError as e:
self.app.logger.error("Error while processing the image, aborting print : %s",str(e))
self.app.logger.error(
"Error while processing the image, aborting print : %s", str(e)
)
raise e
else:
self.app.logger.warning("Not proccessing the image")
@@ -226,7 +243,9 @@ class Printer(object):
try:
self.printer.close()
except Exception as e:
self.app.logger.error("Could not close the printer connexion %s", str(e))
self.app.logger.error(
"Could not close the printer connexion %s", str(e)
)
raise RuntimeError("Could not close the printer connexion. ") from e
self.app.logger.info("Printed a picture")
@@ -237,7 +256,7 @@ class Printer(object):
self.printer.open(self.usb_args)
self.printer.qr(content, center=True)
self.printer.close()
except Exception as e:
except RuntimeError as e:
self.printer.close()
self.app.logger.error(str(e))
return False
@@ -261,11 +280,13 @@ class Printer(object):
def print_task(self, task_type, data):
"""Execute actual print based on task type"""
match (task_type.value):
case ("text"):
self._print_sms(data["txt"],signature=data["sign"])
case ("image"):
self._print_img(data["img"], signature=data["sign"],process=data["process"])
case ("cut"):
case "text":
self._print_sms(data["txt"], signature=data["sign"])
case "image":
self._print_img(
data["img"], signature=data["sign"], process=data["process"]
)
case "cut":
self._cut()
case _:
raise RuntimeError("This task type is not supported")
@@ -289,7 +310,8 @@ def _process_image(self, path):
self.app.logger.debug("Resized the image")
# # Convert to grayscale for dithering
# dithered_img = original_img.convert("L").convert("1") # Dithering using default method (FloydSteinberg)
# dithered_img = original_img.convert("L").convert("1")
# Dithering using default method (FloydSteinberg)
# self.app.logger.debug("Dithered the image")
# Compute brightness of original image (grayscale average)
@@ -323,92 +345,3 @@ def _process_image(self, path):
self.app.logger.debug("Processed and saved image.")
return jpeg_path
def discover_printers():
"""
We try to find all the connected printers ( 0 or n ) to this system.
For every type of supported printer, we try to autodiscover them.
http://www.linux-usb.org/usb.ids A list of USB vendor IDs
04b8 Seiko Epson Corp.
04f9 Brother Industries, Ltd
"""
def find_and_parse_borther_ql_printer():
## We might be able to no use this because there is a `discover` command in https://github.com/pklaus/brother_ql#usage
## Code stolen from https://framagit.org/stickoeur/diagnostickoeur/-/blob/no-masters/printit.py?ref_type=heads
"""Find and parse Brother QL printer information."""
model_manager = ModelsManager()
# Debug print to show we're searching
# print("Searching for Brother QL printer...")
for backend_name in ["pyusb", "linux_kernel"]:
try:
#print(f"Trying backend: {backend_name}")
backend = backend_factory(backend_name)
available_devices = backend["list_available_devices"]()
#print(f"Found {len(available_devices)} devices with {backend_name} backend")
for printer in available_devices:
#print(f"Found device: {printer}")
identifier = printer["identifier"]
parts = identifier.split("/")
if len(parts) < 4:
#print(f"Skipping device with invalid identifier format: {identifier}")
continue
protocol = parts[0]
device_info = parts[2]
serial_number = parts[3]
try:
vendor_id, product_id = device_info.split(":")
except ValueError:
#print(f"Invalid device info format: {device_info}")
continue
# Default model
model = "QL-570"
# Try to match product ID to determine actual model
try:
product_id_int = int(product_id, 16)
for m in model_manager.iter_elements():
if m.product_id == product_id_int:
model = m.identifier
break
#print(f"Matched printer model: {model}")
except ValueError:
#print(f"Invalid product ID format: {product_id}")
continue
printer_info = {
"identifier": identifier,
"backend": backend_name,
"model": model,
"protocol": protocol,
"vendor_id": vendor_id,
"product_id": product_id,
"serial_number": serial_number,
}
#print(f"Found printer: {printer_info}")
return printer_info
except Exception as e:
#print(f"Error with backend {backend_name}: {str(e)}")
continue
print("No Brother QL printer found")
return None
def fint_and_parse_epson_printer():
pass

View File

@@ -1,13 +1,21 @@
from flask_socketio import SocketIO
from gpiozero import Button, LED, DigitalOutputDevice
from time import sleep, gmtime, strftime
from PIL import Image
"""
This class executes when we are on a raspberry Pi.
It handles the press of a button via GPIO,
activates a flash and prints out the picture
that was taken via a USB Webcam.
"""
import io # To check if we are on a Raspberry Pi
import subprocess
import os
from time import sleep, gmtime, strftime
from flask_socketio import SocketIO
from gpiozero import Button, LED, DigitalOutputDevice
from PIL import Image
from task import TextTask, ImageTask, CutTask
class Raspberry(object):
class Raspberry():
"""
This class will manage three things :
- Connecting to a USB webcam
@@ -19,7 +27,7 @@ class Raspberry(object):
def __init__(
self,
printer,
print_queue,
app,
socketio,
button_gpio_port_number,
@@ -27,7 +35,7 @@ class Raspberry(object):
flash_gpio_port_number,
is_flash_present,
):
self.printer = printer
self.print_queue = print_queue
self.socketio = socketio
self.app = app
@@ -38,9 +46,13 @@ class Raspberry(object):
self.image_path = self.app.config["UPLOAD_FOLDER"] + "/image.jpg"
def is_raspberry_pi(self, raise_on_errors=False):
"""
Checking if we are on a Raspberry Pi by checking
information on the /proc/cpuinfo file
"""
# Check if we are running on a raspberry pi
try:
with io.open("/proc/cpuinfo", "r") as cpuinfo:
with io.open("/proc/cpuinfo", "r", encoding="utf-8") as cpuinfo:
found = False
for line in cpuinfo:
if line.startswith("Hardware"):
@@ -141,7 +153,7 @@ class Raspberry(object):
f"Unable to take a picture. Error: {e.stderr.decode()}"
)
return False
except Exception as e:
except RuntimeError as e:
# Catch any unexpected errors
self.app.logger.error(f"Unexpected error while taking picture: {str(e)}")
return False
@@ -198,7 +210,7 @@ class Raspberry(object):
output_path = image_path # Overwrite the original image if no output path is given
image.save(output_path)
except Exception as e:
except RuntimeError as e:
self.app.logger.error(f"Error overlaying logo: {e}")
return False
@@ -225,7 +237,7 @@ class Raspberry(object):
image.save(output_path)
except Exception as e:
except RuntimeError as e:
self.app.logger.error(f"Error cropping image to square: {e}")
return False
@@ -242,7 +254,7 @@ class Raspberry(object):
try:
self.flash.on()
self.take_picture()
except Exception as e:
except RuntimeError as e:
self.app.logger.error(
"Could not take a picture after the button press : " + str(e)
)
@@ -251,15 +263,11 @@ class Raspberry(object):
self.app.logger.debug("Printing picture")
self.led.on()
self.crop_to_square(self.image_path)
self.printer.print_img("src/static/images/extase-club.png", process=True)
self.printer.print_img(self.image_path, process=True)
self.printer.print_sms("")
self.printer.print_sms("With Love From Société.Vide", signature="", bold=True)
self.printer.print_sms("Printed by LittlePrynter", signature="")
self.printer.print_sms("n07070.xyz", signature="")
self.printer.print_sms(strftime("%Y-%m-%d %H:%M", gmtime()), signature="")
self.printer.qr("https://n07070.xyz/articles/littleprynter")
self.printer.cut()
self.print_queue.enqueue(ImageTask(self.image_path,signature="",process=True))
self.print_queue.enqueue(TextTask(content="Imprimé par LittlePrynter", signature=""))
time = strftime("%Y-%m-%d %H:%M", gmtime())
self.print_queue.enqueue(TextTask(content=time, signature=""))
self.print_queue.enqueue(CutTask())
self.led.off()
self.app.logger.debug("Done printing picture")
self.app.logger.debug("Added a photomaton picture to the print queue")
return True

View File

@@ -1,27 +1,32 @@
# Here we define the types of tasks
# We are using Abstract Base Classes,
# like this we can define types of tasks ( text, images, ... )
# that all work with the same basic options
"""
Here we define the types of tasks
We are using Abstract Base Classes,
like this we can define types of tasks ( text, images, ... )
that all work with the same basic options
# The tasks are going to be injected into a Queue.
# It's a usefull way of storing information in our
# program, while making sure that things are indeed printed.
# It's also a way to prevent two concurrent connexions creating
# a access conflict on a single printer, like two people wanting
# to print at the same time.
# We can also delay and store printing tasks until a printer becomes
# available if none is online.
The tasks are going to be injected into a Queue.
It's a usefull way of storing information in our
program, while making sure that things are indeed printed.
It's also a way to prevent two concurrent connexions creating
a access conflict on a single printer, like two people wanting
to print at the same time.
We can also delay and store printing tasks until a printer becomes
available if none is online.
"""
from abc import ABC, abstractmethod
## See https://docs.python.org/3/library/abc.html to learn more about this
# from dataclasses import dataclass
from enum import Enum
import uuid
## You can expand this if you want to take other types of tasks into account
class TaskType(Enum):
"""
The different tasks supported by the printers
"""
TEXT = "text"
IMAGE = "image"
CUT = "cut"
@@ -31,6 +36,7 @@ class PrintTask(ABC):
"""
A print task holds information about what we are looking to print.
"""
def __init__(self, task_type):
self.task_id = self._generate_id()
self.task_type = task_type
@@ -41,7 +47,7 @@ class PrintTask(ABC):
@abstractmethod
def get_print_data(self):
"""Return data formatted for printer"""
pass
def _generate_id(self):
# Generate unique task ID
@@ -52,18 +58,21 @@ class TextTask(PrintTask):
"""
This tasks represents a texte content, and it's signature.
"""
def __init__(self, content, signature):
super().__init__(TaskType.TEXT)
self.content = content
self.signature = signature
def get_print_data(self):
return { "txt": self.content, "sign": self.signature }
return {"txt": self.content, "sign": self.signature}
class ImageTask(PrintTask):
"""
This tasks represents a image content ( in the form of it's path ), and it's signature.
"""
def __init__(self, image_path, signature, process):
super().__init__(TaskType.IMAGE)
self.image_path = image_path
@@ -72,7 +81,8 @@ class ImageTask(PrintTask):
def get_print_data(self):
# Return image data in printer-compatible format
return { "img": self.image_path, "sign": self.signature, "process" : self.process }
return {"img": self.image_path, "sign": self.signature, "process": self.process}
class CutTask(PrintTask):
"""

View File

@@ -1,41 +1,41 @@
class User(object):
"""docstring for User."""
# class User(object):
# """docstring for User."""
def __init__(self, arg):
super(User, self).__init__()
self.arg = arg
# def __init__(self, arg):
# super(User, self).__init__()
# self.arg = arg
# @app.route('/login', methods=['POST','GET'])
# @limiter.limit("100 per minute", error_message=error_handler_limiter)
def login():
if request.method == "POST":
if not session.get("logged_in"):
if request.form["username"] and request.form["password"]:
# Get the json
with open("users.json") as f:
users_file = json.load(f)
for user in users_file["users"]:
if users_file["users"][user] == request.form["password"]:
session["logged_in"] = True
session["user"] = request.form["username"]
# # @app.route('/login', methods=['POST','GET'])
# # @limiter.limit("100 per minute", error_message=error_handler_limiter)
# def login():
# if request.method == "POST":
# if not session.get("logged_in"):
# if request.form["username"] and request.form["password"]:
# # Get the json
# with open("users.json") as f:
# users_file = json.load(f)
# for user in users_file["users"]:
# if users_file["users"][user] == request.form["password"]:
# session["logged_in"] = True
# session["user"] = request.form["username"]
if not session.get("logged_in"):
flash("Mot de passe ou pseudo invalide.", "danger")
return redirect(url_for("login"))
else:
return redirect(url_for("display_index_page"))
else:
flash("Incorrect logins")
return render_template("password.html")
else:
return render_template("password.html")
else:
return render_template("password.html")
# if not session.get("logged_in"):
# flash("Mot de passe ou pseudo invalide.", "danger")
# return redirect(url_for("login"))
# else:
# return redirect(url_for("display_index_page"))
# else:
# flash("Incorrect logins")
# return render_template("password.html")
# else:
# return render_template("password.html")
# else:
# return render_template("password.html")
@app.route("/logout")
def logout():
session["logged_in"] = False
flash("Tu est déconnecté", "info")
return redirect(url_for("login"))
# @app.route("/logout")
# def logout():
# session["logged_in"] = False
# flash("Tu est déconnecté", "info")
# return redirect(url_for("login"))

View File

@@ -6,7 +6,8 @@ from task import TextTask, ImageTask, CutTask
class Web(object):
"""Web is the class that gets all of the information from web calls ( API and Web page ) and provides checks before sending stuff to printing"""
"""Web is the class that gets all of the information from web calls
( API and Web page ) and provides checks before sending stuff to printing"""
def __init__(self, app, print_queue):
super(Web).__init__()
@@ -30,7 +31,7 @@ class Web(object):
except Exception as e:
self.app.logger.error(e)
raise RuntimeError("Could not add SMS to queue, " + str(e)) from e
self.app.logger.info("Added two new tasks at position %s and %s", sms, cut )
self.app.logger.info("Added two new tasks at position %s and %s", sms, cut)
return True
def print_image(self, image, sign: str) -> bool:
@@ -46,19 +47,22 @@ class Web(object):
if file_uploaded:
self.app.logger.debug("File has been uploaded, printing...")
try:
img = self.print_queue.enqueue(ImageTask(os.path.join(
img = self.print_queue.enqueue(
ImageTask(
os.path.join(
self.app.config["UPLOAD_FOLDER"],
secure_filename(image.filename),
),
signature=sign,
process=True))
process=True,
)
)
cut = self.print_queue.enqueue(CutTask())
except Exception as e:
raise RuntimeError("Could not add IMG to queue" + str(e)) from e
self.app.logger.info("Added two new tasks at position %s and %s", img, cut )
self.app.logger.info("Added two new tasks at position %s and %s", img, cut)
return True
@@ -96,10 +100,14 @@ class Web(object):
)
return True
else:
self.app.logger.error("Could not save file because the filename is forbidden")
self.app.logger.error(
"Could not save file because the filename is forbidden"
)
return False
else:
self.app.logger.error("Could not save file, it seems to be null ? : " + str(filename))
self.app.logger.error(
"Could not save file, it seems to be null ? : " + str(filename)
)
return False
def get_queue_state(self):

View File

@@ -4,7 +4,7 @@
import threading
import time
from task import TaskType
class PrintWorker(threading.Thread):
def __init__(self, app, print_queue, printer, socketio=None):
@@ -22,23 +22,17 @@ class PrintWorker(threading.Thread):
"""Background thread that processes queue items"""
self.app.logger.info("Worker started working.")
while True:
if not self.running:
if not self.running or not self.printer.ready:
time.sleep(0.2)
continue
# TODO: This could be improved to simply no start
# the while loop as long as the printer is not ready.
# and maybe get out of it when the printer is not ready anymore ?
if not self.printer.ready:
self.app.logger.debug("Waiting for the printer to be ready...")
time.sleep(1)
continue
try:
task = self.print_queue.dequeue()
except Exception as e:
self.app.logger.error("Could not get a new task ! %s ", str(e))
raise RuntimeError("We could not get a new task because " + str(e)) from e
raise RuntimeError(
"We could not get a new task because " + str(e)
) from e
if task:
try:
@@ -51,7 +45,7 @@ class PrintWorker(threading.Thread):
print_data = task.get_print_data()
try:
self.printer.print_task(task.task_type, print_data)
except Exception as e:
except RuntimeError as e:
self.app.logger.error("Could not print : %s", str(e))
raise e
@@ -59,7 +53,7 @@ class PrintWorker(threading.Thread):
self.print_queue.mark_completed(task.task_id, "completed")
self._emit_status(task.task_id, "completed")
except Exception as e:
except RuntimeError as e:
task.status = "failed"
self.print_queue.mark_completed(task.task_id, "failed")
self._emit_status(task.task_id, "failed", error=str(e))
@@ -78,18 +72,19 @@ class PrintWorker(threading.Thread):
data = {
"task_id": task_id,
"status": status,
"position": None # Task no longer in queue
"position": None, # Task no longer in queue
}
if error:
data["error"] = error
self.socketio.emit('task_status', data, room=room)
self.socketio.emit("task_status", data, room=room)
def stop_worker(self):
"""
Give the worker a break
"""
self.app.logger.debug("Giving the worker a break")
self.state = "drinking-a-beer"
self.running = False
@@ -97,6 +92,7 @@ class PrintWorker(threading.Thread):
"""
Get the worker back to it
"""
self.app.logger.debug("Time to work !")
self.state = "idle"
self.running = True
@@ -107,5 +103,5 @@ class PrintWorker(threading.Thread):
return {
"is_running": self.running,
"queue_size": len(self.print_queue),
"state" : self.state
"state": self.state,
}